This page is on Fractions for Pharmacy Techs.
Understanding fractions is an important skill when you're working as a Pharmacy Technician.
We're going to go over some quick guidelines that will help you remember how to work with fractions and convert fractions into decimals.
When you're looking at a fraction, the number on top is called the numerator and the number on the bottom is the denominator.
This means if you're dealing with one-half (1/2), the numerator is 1 and the denominator is 2. If you're adding fractions that have the same denominator, you simply add the numerators together and keep the same denominator. For example:
In this case we simply add 2+3 to get 5, and the denominator is still 6. If we want to add fractions that have a different denominator, then we need to convert them so that they both have the same denominator. For example:
In this case, to find a common denominator we multiply them by the other denominator. So we're going to multiply 1/4 by 3/3 and 1/3 by 4/4.
Subtracting fractions works the same way. We simply subtract the numerators as long as the denominators are the same.
If the denominators are different, we use the same process as above to find a common denominator and then subtract.
To multiply fractions, you can simply multiply straight across both lines. That is, you multiply the numerators and the product is the new numerator. You multiply the denominators and the product is the new denominator. For example:
1/2 * 1/2 = 1/4
1/4 * 1/4 = 1/16
In order to divide fractions, simply reverse the second number and then multiply across. 1/3 divided by 1/4 then becomes:
1/3 * 4/1 = 4/3
Once you're finished adding, subtracting and multiplying to get your result, you can see if it's possible to reduce your fraction to a more simple form. For example:
These are all ways to write one-half. But 1/2 is the simplest form of this answer.
To reduce a fraction, simply factor out the same number from the numerator and the denominator. If the numerator is 1, it cannot be reduced.
Finally, to convert from a fraction to a decimal, divide the numerator by the denominator. To convert one-half, you would divide 1 by 2 and your result is:
Here are some common fractions converted into decimals:
1/2 = 0.5
1/3 = 0.333
1/4 = 0.25
1/5 = 0.2
1/6 = 0.166
If you ever get confused when looking at a fraction that you need to do math with, just start with the first step and do everything slowly and in order.
When you're done, double check your work for basic logic. For example, if you're adding 1/2 and 1/4, you know that the final answer needs to be less than 1 but greater than one-half.
So 3/4 or .75 passes our logic test and is also the correct answer. Fractions are much easier when you take each step in order and take the extra time to double check your work.